--- title: Explained: AdBlue in a Diesel Tank Wherry Town canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/wherry-town-cornwall/ location: Wherry Town county: Cornwall latitude: 50.111340 longitude: -5.547030 service: AdBlue in a Diesel Tank updated: 2026-10-03 --- # Why It Happens and How to Avoid It: AdBlue in a Diesel Tank in Wherry Town Stop here for a moment if the diesel tank already has AdBlue in it: ignition off, engine off, and phone 0333 366 0103. A drain plus a full flush, carried out right where your vehicle stands around Wherry Town, is usually all it needs if found before the motor runs. The rest of this page explains why it happens and how to make sure it doesn't — useful if you're reading before it has happened. ## Two fillers, two tanks: AdBlue in a diesel vehicle Many modern diesels in Trereife, like those in Wherry Town, run on two fluids; the engine gets just the diesel. Stored in a tank of its own, AdBlue is sprayed into the exhaust stream and cleans it. Each tank comes with a filler of its own. Under one flap, side by side: that is the arrangement on many vehicles. Elsewhere, AdBlue's filler sits under the bonnet or in the boot instead. The diesel side is fuelled at the petrol pump all the time. A driver who has to stop and think where it goes normally tops up the AdBlue side, from a bottle, and far less commonly. That gap is where the error lives. ## Wherry Town: how AdBlue in your diesel tank happens It's seldom carelessness. Three things tend to line up. To start with, the warning. Low AdBlue brings a message from the vehicle, and running out leads to limp mode — hence a hurried top-up, perhaps before work off Lariggan Crescent, or at Alexandra Inn on the way home that evening. Unfamiliar cars come next, too. Hire cars, new cars and company motors put their fillers in new places, and the hand reaches for the cap it used on the old one. And the bottle fits. A bottle with a spout goes into a diesel filler as easily as an AdBlue one, and so nothing stops the tip once it has started. It takes a few seconds, whether out in Alverton or right in the centre of Wherry Town. ## Which filler is for AdBlue, and which for diesel? Look at these before pouring, at a forecourt in Wherry Town or a drive over in Tredavoe. Seconds, that's all. - Read the cap instead of going by position: AdBlue caps are commonly blue or marked "AdBlue", and diesel caps usually aren't. - Many motors fit AdBlue the smaller neck of the two. - Look inside your fuel flap: many vehicles carry a label there saying which fuel goes where. - In your boot or under the bonnet: that's where the filler is if it is not by your diesel cap, and the handbook tells you which. - Check with the person who drove it last — before you leave, not when the light comes on — if you pick up a hire or company car from somewhere like the car park outside Penzance. ## Topping up AdBlue without it reaching the diesel tank A routine for the day the light comes on, wherever across Cornwall that is. - Park then switch off. Not on a slope, not with the engine running, and not in a rush on the side of Alexandra Terrace. - Locate the AdBlue filler, read the cap, and say the word "AdBlue" out loud as unscrewing it. It seems silly. It does the trick. - If both sit under one flap, check the diesel cap is still closed before you lift the bottle — then leave it on. - Pour slowly, using the bottle's own spout. Stop when it is full or when the bottle is empty. - Only after that, start your car: close the cap, check again, and make sure the diesel cap was never opened. If at stage two or three you find you have already poured into your diesel side, stop there. Never go on to step five. ## AdBlue in the diesel tank already, around Wherry Town? Then the order of things is short. Do not start your motor. Leave your ignition off too, because on plenty of diesels switching it on by itself starts the pump. AdBlue doesn't mix with diesel — it sinks to the bottom of your tank, where your fuel is pulled from — so do not top up with diesel to dilute it. On a forecourt — Texaco, Tesco or any other — the staff will normally help push the car away, if you ask. If you are on your own drive in Wherry Town, leave it where it sits. Already run? Stop once it's safe, then switch off. The next exit means the place to leave when you're on the M5, over 50 miles from Wherry Town. Distance matters — a short hop across Wherry Town is a smaller job than driving under 25 miles to Truro — so tell us about how far it went. ## When our engineers arrive in Wherry Town, what occurs? Our engineers come to the car wherever it has stopped, whether that's outside Alverton Primary School, near Newlyn Orion Gallery or on your own drive. Our technicians ask what was put in, about how much, and if it has run, since the replies settle this work and our quote. The price is given over the phone, before any van leaves. Next: draining, then a thorough flush of the entire system. With AdBlue that counts more than with petrol: it crystallises and is corrosive to some of the metals in a fuel system, so it does not wash out on its own. The fuel filter is flushed, or replaced where it needs to be; clean diesel goes in; and the vehicle is tested. The motor is fired up next and tested to make sure it runs properly, all before we leave. If your motor has not run, most jobs take about half an hour once we're there, using pumps that are safe on a working forecourt and quiet enough to use outside a house at night. You pay on the day, with nothing upfront, and get a VAT invoice and an engineer report for your insurer. It is worth checking your policy as the van travels to you: misfuelling cover is included with plenty of policies. ## About Wherry Town, briefly Wherry Town is a coastal locality in Cornwall, situated near the towns of Penzance and Newlyn, with Alverton to the east. Wherry Town has a population of around 1724 people and is characterised by detached housing. Wherry Town sits at a low elevation of 18 metres above sea level, close to the sea. Wherry Town is approximately 24 miles from the city of Truro and 255 miles from London. ## AdBlue drains around Wherry Town and across Cornwall Newlyn and Penzance are among the towns around Wherry Town, a coastal area, that the same vans cover, over TR postcodes. The van gets to you fastest with a postcode starting TR18 4. Moving your car isn't needed. Anywhere it sits — beside Fisherman Statue Memorial - 'Throw Me A Line', on a lay-by en route to Mann's Field, at home — that's where it gets emptied. If you are close to a border, or somewhere hard to explain like the back of St. Peter's Church, ring and ask instead of guessing. ## Wherry Town motorists: the short version Before you tip, read the cap. AdBlue in the diesel tank after all? Keep it off then ring 0333 366 0103; Petrol in Diesel drains it on the spot, throughout Cornwall.